I am far from being a great power fisherman... ie moving baits like cranks but as far as I can tell you have 2 basic questions.
1. What colors to use?
2. What depth should I fish?
For the first question it is difficult to answer. First baitfish color choices are typically good in just about any lakes but there are other forage bases present. Bream/bluegill/sunfish are common in most every lake. They represent a big part of a basses diet so this would be a logical choice. Also perch patterns seem to do well even in lakes where perch aren't present. If the lakes you fish have rock, they likely will have crayfish. There are many crayfish colored crank baits that will work well on rock bottoms. Second water clarity may dictate color choice. The less clarity the more visible the color choice while the clearer the water the more natural colors.
For the second question I would suggest getting a good map of the lakes you fish. Figure out where key pieces of structure are... like points, drop offs, creek channels, brush piles, areas that have rocks, weeds, and brush together etc. Target these areas by breaking down the water column into different layers.
1. Shallow cranks
2. Medium cranks
3. Deeper cranks
4. Lipless cranks like rattle traps
5. Suspending jerkbaits
Buy a few of each of theses types to use for different situations. This will get you started with crankbait fishing. Do some experimenting to get a feel for what works best.
However my best advice would be to learn plastics fishing as soon as you feel comfortable with it. I realize this is the area with numerous techniques and confusion exists but 9 times out of 10 I catch more and better fish on these baits. Since you are a former trout angler you will likely have the patience for it just need to get the techniques down.
Also note that crankbaits and the treble hook baits seem to fish best with a rod with medium to medium heavy power and moderate action. This type of rod will have a bit more give in the blank to keep fish pinned in order to prevent the hooks from ripping out.
The other piece of advice would be to read as much as you can. Do Google searches for crankbait fishing and also read as many articles as you can. You can start with this site and go from there.
Good luck